scholarly journals Utilization of Industrial Effluent for Irrigation - Pros and Cons

2015 ◽  
Vol 37 ◽  
pp. 78-81
Author(s):  
S. David Noel ◽  
M.R. Rajan
Keyword(s):  
Water Level ◽  
Human Health ◽  
Surface Waters ◽  
Technological Development ◽  
Industrial Effluent ◽  
Aquatic Organisms ◽  
Toxic Substances ◽  
Global Issue ◽  
Pros And Cons ◽  
Alternative Sources

Decreasing water level and shortage of water is being a major problem worldwide. For agriculture purpose this problem gives rise to the use of alternative sources of water. Most of these water sources are affected by the discharge waste of effluent from various types of industries like mining, textiles, chemical etc. Due to reason this effluent may contains many organic toxic substances that could have hazardous impact on human health. In addition, technological development has contributed to increase other industrial dumping that contaminates surface waters. The irregular disposal of industrial effluent has created pollution problems since this effluent is disseminated in the environment or is accumulated in sediments, aquatic organisms, and water. In this paper a solution for this global issue has been addressed and strategies have been suggested for this problem.

scholarly journals Denitrification Control in a Recirculating Aquaculture System—A Simulation Study

Processes ◽  
2020 ◽  
Vol 8 (10) ◽  
pp. 1306
Author(s):  
Pedro Almeida ◽  
Laurent Dewasme ◽  
Alain Vande Wouwer
Keyword(s):  
Carbon Source ◽  
Carbon Sources ◽  
Aquatic Organisms ◽  
Operating Conditions ◽  
Toxic Substances ◽  
Recirculating Aquaculture System ◽  
Treatment Technology ◽  
Tuning Method ◽  
Recirculating Aquaculture ◽  
Aquaculture System

The recirculating aquaculture system (RAS) is a land-based water treatment technology, which allows for farming aquatic organisms, such as fish, by reusing the water in the production (often less than 5%). This technology is based on the use of filters, either mechanical or biological, and can, in principle, be used for any species grown in aquaculture. Due to the low recirculation rate, ammonia accumulates in the system and must be converted into nitrate using nitrification reactors. Although less toxic for fish, nitrate can also be further reduced into nitrogen gas by the use of denitrification biofilters which may create several issues, such as incomplete denitrification, resulting in toxic substances, such as nitrite and nitric oxide, or a waste of carbon source in excess. Control of the added quantity of carbon source in the denitrification biofilter is then mandatory to keep nitrate/nitrite concentrations under toxic levels for fish and in accordance with local effluent regulations, and to reduce costs related to wasted organic carbon sources. This study therefore investigates the application of different control methodologies to a denitrification reactor in a RAS. To this end, a numerical simulator is built to predict the RAS behavior and to allow for the comparison of different control approaches, in the presence of changes in the operating conditions, such as fish density and biofilter removal efficiency. First, a classical proportional-integral-derivative (PID) controller was designed, based on an SIMC tuning method depending on the amount of ammonia excreted by fish. Then, linearizing and cascade controllers were considered as possible alternatives.

Chromium in the Canadian environment

1995 ◽  
Vol 3 (1) ◽  
pp. 121-144 ◽  
Author(s):  
Jerome O. Nriagu ◽  
Abdul Kabir
Keyword(s):  
Human Health ◽  
Health Effects ◽  
Surface Waters ◽  
Soil Microorganisms ◽  
Local Scale ◽  
Aquatic Biota ◽  
Chromium Toxicity ◽  
Toxicity Threshold ◽  
Environmental Media ◽  
Human Health Effects

The widening use of chromium and its compounds by local industries has led to a growing concern about the effects of chromium contamination on the Canadian environment. This report summarizes the data on Canadian sources and the concentrations of chromium in air, water, sediments, soil, terrestrial wildlife and aquatic biota. It reviews what little is currently known about the cycling of chromium in Canadian ecoystems, and the need for measuring Cr(III) and Cr(VI) rather than total Cr in the environmental media is emphasized. The potential effects of elevated levels of chromium on plants, soil microorganisms, wildlife, and aquatic biota are discussed. The human health effects are not covered. The conclusion is reached that chromium pollution has become a threat to Canadian ecosystems, especially at the local scale where the ambient chromium concentrations in some surface waters, sediments, and soils are now close to or above the toxicity threshold for a number of the more sensistive organisms.Key words: chromium pollution, chromium toxicity, chromium chemistry, chromium emission, bioaccumulation of chromium.

scholarly journals Risk Assessment of Malakite with the Active Substances Dithianon and Pyrimenthanil

2019 ◽  
pp. 312-314
Author(s):  
Torsten Källqvist ◽  
Merete Grung ◽  
Katrine Borgå ◽  
Hubert Dirven ◽  
Ole Martin Eklo ◽  
...  
Keyword(s):  
Risk Assessment ◽  
Surface Waters ◽  
Plant Protection ◽  
Aquatic Organisms ◽  
Toxicity Tests ◽  
Concentration Addition ◽  
Active Ingredients ◽  
Active Substances ◽  
Assessment Factor

The plant protection product Malakite (BAS 669 01 F), containing the active substances dithianon and pyrimethanil, is a fungicide against scab in pome fruits. Products containing these active plant protection substances are approved in Norway, but not with both substances in the same product. The Swedish Chemicals Agency (KemI) has as zonal Rapporteur Member State (zRMS) of the Northern Zone evaluated the product Malakite and decided on non-approval due to the observation of unacceptable effects in exposed birds, aquatic organisms, non-target arthropods and earthworms. On request from The Norwegian Food Safety Authority, the VKM Panel on Plant Protection Products has discussed the available data and the report prepared by KemI, and has concluded as follows on the questions raised: On the refinement of DT50 in long term risk assessment for birds: It is the view of the VKM panel that the refinement is not acceptable because the analysis using first order kinetics seems not in line with a realistic and sufficiently conservative approach for the data provided. Furthermore, field studies from more sites are required. On the long term cumulative effects of the active substances on birds: VKM shares the view of KemI, that the combined sub-lethal and reproduction effects should be assessed because the mode of action of the two ingredients has only been shown in fungi, and since the mechanisms in birds could be different. On the reduction of assessment factor for fish: VKM opposes to the reduction of assessment factor for dithianon in fish because the data from acute toxicity tests cannot be extrapolated to chronic toxicity, and because the factor should reflect not only the variation in interspecies sensitivity, but also the uncertainty involved in extrapolation from laboratory tests to the field situation. On the choice of end point in risk assessment for fish: The VKM panel considers the NOEC of dithianon for fish determined from the study at pH 7.9 not to be adequate for the more acidic Norwegian surface waters, and recommends using the data from the test performed at pH 6.5. On the formulation studies for aquatic organisms: It is the opinion of the VKM panel that the formulation studies may be used together with corresponding studies with the active ingredients as long as the studies compared are performed and evaluated according to the same principles. However, VKM notes that the formulation tests as well as the tests of the active ingredients have been performed at high pH values, which are not representative to most Norwegian surface waters. Thus, the toxic effect of dithianon shown in these tests are likely to be lower than expected under typical conditions in Norway. On the assessment factors for concentration addition in fish: It is the opinion of the VKM panel that a reduction in assessment factor for one component in a mixture cannot be used for a formulation containing components for which a similar reduction has not been accepted. On effect studies of active substances and formulations on non-target arthropods: The VKM panel shares the view of KemI that the risk assessment should be based on all available information, including the studies presented for the active substances. On the endpoint in earthworm risk assessment: VKM supports the view of KemI that the observed effects of pyrimethanil on reproduction of earthworms should be considered in the risk assessment of Malakite.

scholarly journals Human Health Risk Assessment of The Levels of Dioxin-Like Polychlorinated Biphenyls (PCBs) in Soils From Mechanic Workshops Within Nekede Mechanic Village, Imo State, Nigeria

2021 ◽  
Author(s):  
Victor Chukwuemeka Eze ◽  
Azuka Nwabudike ◽  
Chidi Duru ◽  
Beniah Isiuku ◽  
Francis Ibe ◽  
...  
Keyword(s):  
Health Risk ◽  
Polychlorinated Biphenyls ◽  
Human Health ◽  
Organic Pollutant ◽  
Human Health Risk ◽  
Control Sample ◽  
Sampling Point ◽  
Toxic Substances ◽  
Imo State ◽  
Pet Bottles

Abstract Dioxin-like polychlorinated biphenyls (DL-PCBs) are a class of persistent toxic substances with a high potential to accumulate in the soil as an organic pollutant and bioaccumulate in humans. The study determined the level and human health risk of twelve (12) DL-PCBs in soils from mechanic workshops within Nekede mechanic village (NMV), Imo State. In this study, soil samples (0–15 cm depth) were collected at four different sampling points within Nekede mechanic village. At each sampling point, composite samples consisting of 10 sub-samples were collected with pre-cleaned pet bottles using soil auger and were labeled SA, SB, SC, SD. Control sample was taken 500 metres away from the mechanic village where there was no form of auto-mechanic activities. Sample analysis was conducted using Agilent GC 6890N coupled with Agilent MS 5970B to determine the levels of DL-PCBs. The data were analyzed using SPSS version 23. The results revealed that the mean concentration of 12 DL-PCB congeners (Σ12PCBs) in soil ranged from 0.31–16.31 µg kg− 1, which was much higher than that in the control sample (0.006–0.087 µg kg− 1). PCB-126 was the major contributor (58.99%) while the least contributor was PCB-157 (0.0040%) of the Σ12 DL-PCBs TEQ. The estimated LCR (adults 1.29×101, children 4.42×101) and HQs (adults 6.68×102, children 2.29×103) were above the acceptable risk limit (LCR = 10− 4, HQ = 1); indicating a very high adverse effect of DL-PCBs on humans especially children.

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